The overarching objective of the Biostatistics Shared Resource (BSR) is to establish and maintain the highest possible standards of statistical and scientific quality in the cancer research conducted by the NCCC research investigators. Specific aims include providing ready access to expert statistical consultation and analysis for all NCCC scientists, providing sound design advice and statistical review for all clinical protocols, monitoring the statistical quality of ongoing studies, and overseeing statistical data management. The Resource is staffed by five faculty statisticians and two statistical analysts. Data management activities are coordinated with the Informatics Shared Resource and the Clinical Research Office. The BSR Director serves on the NCCC Clinical Cancer Research Committee and the Cancer Research Committee, and the BSR Associate Director for Clinical Studies serves on the Safety and Data Monitoring Committee. Ml BSR faculty members are actively involved in NCCC Research Programs and are collaborators on numerous peer- reviewed funded research projects. Areas of faculty statistical expertise and methodological research, supported in part by NCI R0ls, include longitudinal data analysis and study design, measurement error methods in clinical research and epidemiology, clustered data method for family studies, covariate adjustment in randomized trials, quality-of-life measures in cancer clinical trials, and clinical decision modeling and diagnostic test assessment.